Ups the question of a response.
The US has reportedly identified locations in Iran from which drones and cruise missiles were launched against major Saudi oil facilities on Saturday.
Senior US officials told media outlets that the locations were in southern Iran, at the northern end of the Gulf.
Saudi air defences did not stop the drones and missiles because they were pointed southwards, to prevent attacks from Yemen, they added.
Iran denies involvement in the attacks, which disrupted global oil supplies.
Yemen’s Iran-aligned Houthi rebels said they had launched the drones that struck the Abqaiq oil processing plant, the world’s largest, and the Khurais oilfield.